fix: allow buildFromSdist to ignore Rust drvs

[srid]

Resolves #292 as a hack, but what is the proper fix here for notorious (#293) buildFromSdist?

[srid]

Closing in favour of #298

[roberth]

ignore Rust drvs

I thought I could ignore this but it freaks me out, somehow.

Is it really necessary to do this?
If there's a good reason to do it this way, it might be acceptable to insert them into the overlay, as a hacky implementation, but in that case please make it a real feature with a separate option, so that it doesn't break by itself, and so that it can be deprecated when a better solution comes along.

[srid]

@roberth This PR got closed without being merged. Not sure what you are referring to. When you said "Is it really necessary to do this?" what are you referring to?

[srid]

@roberth I think you are referring to the regression which is now fixed in #306

[roberth]

When you said "Is it really necessary to do this?" what are you referring to?

Having rust files in the overlay, supporting that.

I apologize if I'm replying to the wrong thread or necrobumping unnecessarily.

[srid]

When you said "Is it really necessary to do this?" what are you referring to?

Having rust files in the overlay, supporting that.

This should be already supported through the custom option; see

https://github.com/shivaraj-bh/haskell-rust-ffi-template/blob/0ea595271103161184332ad4c5322fbc1c93a711/haskell/default.nix#L7

https://nixos.asia/en/haskell-rust-ffi

Do you have a better interface in mind?

(There's a proposal that incidentally gets rid of this custom option; see #285)